// errorcheck // Copyright 2009 The Go Authors. All rights reserved. // Use of this source code is governed by a BSD-style // license that can be found in the LICENSE file. // Verify overflow is detected when using numeric constants. // Does not compile. package main import "unsafe" type I interface{} const ( // assume all types behave similarly to int8/uint8 Int8 int8 = 101 Minus1 int8 = -1 Uint8 uint8 = 102 Const = 103 Float32 float32 = 104.5 Float64 float64 = 105.5 ConstFloat = 106.5 Big float64 = 1e300 String = "abc" Bool = true ) var ( a1 = Int8 * 100 // ERROR "overflow|cannot convert" a2 = Int8 * -1 // OK a3 = Int8 * 1000 // ERROR "overflow|cannot convert" a4 = Int8 * int8(1000) // ERROR "overflow|cannot convert" a5 = int8(Int8 * 1000) // ERROR "overflow|cannot convert" a6 = int8(Int8 * int8(1000)) // ERROR "overflow|cannot convert" a7 = Int8 - 2*Int8 - 2*Int8 // ERROR "overflow|cannot convert" a8 = Int8 * Const / 100 // ERROR "overflow|cannot convert" a9 = Int8 * (Const / 100) // OK b1 = Uint8 * Uint8 // ERROR "overflow|cannot convert" b2 = Uint8 * -1 // ERROR "overflow|cannot convert" b3 = Uint8 - Uint8 // OK b4 = Uint8 - Uint8 - Uint8 // ERROR "overflow|cannot convert" b5 = uint8(^0) // ERROR "overflow|cannot convert" b5a = int64(^0) // OK b6 = ^uint8(0) // OK b6a = ^int64(0) // OK b7 = uint8(Minus1) // ERROR "overflow|cannot convert" b8 = uint8(int8(-1)) // ERROR "overflow|cannot convert" b8a = uint8(-1) // ERROR "overflow|cannot convert" b9 byte = (1 << 10) >> 8 // OK b10 byte = (1 << 10) // ERROR "overflow|cannot convert" b11 byte = (byte(1) << 10) >> 8 // ERROR "overflow|cannot convert" b12 byte = 1000 // ERROR "overflow|cannot convert" b13 byte = byte(1000) // ERROR "overflow|cannot convert" b14 byte = byte(100) * byte(100) // ERROR "overflow|cannot convert" b15 byte = byte(100) * 100 // ERROR "overflow|cannot convert" b16 byte = byte(0) * 1000 // ERROR "overflow|cannot convert" b16a byte = 0 * 1000 // OK b17 byte = byte(0) * byte(1000) // ERROR "overflow|cannot convert" b18 byte = Uint8 / 0 // ERROR "division by zero" c1 float64 = Big c2 float64 = Big * Big // ERROR "overflow|cannot convert" c3 float64 = float64(Big) * Big // ERROR "overflow|cannot convert" c4 = Big * Big // ERROR "overflow|cannot convert" c5 = Big / 0 // ERROR "division by zero" c6 = 1000 % 1e3 // ERROR "invalid operation|expected integer type" ) func f(int) func main() { f(Int8) // ERROR "convert|wrong type|cannot" f(Minus1) // ERROR "convert|wrong type|cannot" f(Uint8) // ERROR "convert|wrong type|cannot" f(Const) // OK f(Float32) // ERROR "convert|wrong type|cannot" f(Float64) // ERROR "convert|wrong type|cannot" f(ConstFloat) // ERROR "truncate" f(ConstFloat - 0.5) // OK f(Big) // ERROR "convert|wrong type|cannot" f(String) // ERROR "convert|wrong type|cannot|incompatible" f(Bool) // ERROR "convert|wrong type|cannot|incompatible" } const ptr = nil // ERROR "const.*nil|not constant" const _ = string([]byte(nil)) // ERROR "is not a? ?constant" const _ = uintptr(unsafe.Pointer((*int)(nil))) // ERROR "is not a? ?constant" const _ = unsafe.Pointer((*int)(nil)) // ERROR "cannot be nil|invalid constant type|is not a constant|not constant" const _ = (*int)(nil) // ERROR "cannot be nil|invalid constant type|is not a constant|not constant"